A composite of MnO2 and poly-o-phenylenediamine (PoPD) was one-step synthesized by co-precipitation with the reaction of KMnO4 and o-phenylenediamine in acidic solution at room temperature. The influence of the addition of cetyl trimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) on the morphology and electrochemical performance was investigated. FT-IR, XRD and SEM were adopted to examine the obtained materials, and the electrochemical properties of the products were characterized by cyclic voltammetry and galvanostatic charge-discharge. The material synthesized in the presence of 2.5 g L-1 had a specific capacitance of 262.2 F g(-1) determined with cyclic voltammetry in a potential window of 0-0.9 V vs. saturated calomel electrode in 1.0 mol L-1 KNO3 solution. (c) 2013 Elsevier Ltd. All rights reserved.